1. Field of the Invention
Detection of specific macromolecular species associated with individual cellular colonies or virus plaques is of crucial importance in molecular cloning, screening of conjugants, or transformed or transduced cells, and the like. Existing methods for detecting either specific nucleic acid sequences or antigens are adequate for many situations, but leave much to be desired when one is searching for the rare event. Screening to be successful should be simple and easily performed, minimize false positives and have a substantial assurance of being able to detect the presence of the mutant or variant of interest.
With the ability to prepare antibodies highly specific for a determinant site, one has the opportunity to specifically bind to a protein which serves as a marker for the presence of a cell or virus. The difficulty still remains in trying to detect an extremely small proportion of a total cellular and/or viral population associated with the protein of interest. Desirably, any technique which employs monoclonal antibodies or polyclonal antibodies should be reasonably rapid, allow for accurate discrimination, permit the screening of large numbers of cells or viruses and provide for isolation of the desired variant organism.
2. Description of the Prior Art
Kaplen, et al. Gene (1981) 13:211; and Kaplan, et al., ibid, (1981) 13:221 describes a method for screening large numbers of bacteriophage microplaques for the presence of specific antigen.